Plant stake



FIG. 1 is a perspective view of a plant stake embodying my new design;

FIG. 2 is a left side elevation thereof, with a right side elevation thereof being a mirror image thereof;

FIG. 3 is a front elevation thereof;

FIG. 4 is a rear elevation thereof;

FIG. 5 is a top plan thereof; and

FIG. 6 is a bottom plan thereof. 

The ornamental design for a plant stake, as shown and described. 